In the prior art various disclosures have been made of fogging nozzles and other types in combination, including those of the following U.S. Patent Nos.:
No. 3,163,363 issued to R. L. Travis on 12-29-64 discloses a nozzle which can provide a straight stream, a hollow cone, a solid cone or a combination of cone and straight-stream;
No. 2,389,642 issued to J. C. Schellin et al, on 11-27-45, discloses a nozzle with variations providing alternatively a straight stream or a conical stream, and in one variation a combination of streams simultaneously;
No. 2,345,813 issued to W. R. Harriman on 4-4-44, discloses a nozzle with swinging mechanism to alter flow;
No. 577,616 issued to E. L. Day on 2-23-97 discloses a nozzle with valve control to emit a conical spray and/or a central stream spray;
No. 575,596 issued to P. J. Doyle on 1-19-97, discloses another form of nozzle which is valve controlled to emit a solid spray, a conical spray, or both;
No. 214,778 issued to C. W. King on 4-29-79, discloses a lawn sprinkler which emits both a conical stream from a rotary portion and a straight jet stream from the central portion;
No. 89,456 issued to A. F. Allen on 4-27-1869 discloses a nozzle controllable to emit both conical and straight through streams, or straight through alone.
However, the old art is believed not to provide the advantages of the present invention apparent in the objects thereof, which include:
to provide firefighters with a new nozzle system giving them the option of 1.) a straight through stream which may be a fogging stream of a conventional fogging nozzle is used on the exhaust end of the invention, of 2.) of the straight through stream in combination with a whirling fogcone, or 3.) shutting off flow.
Translated to advantages such choice will provide for entering a blazing enclosure and avoiding or reducing the hazards of shooting high volume, high velocity fog ahead. These hazards result from the jet-pump effect of the forward directed fog stream which at the same time as it produces high pressure when it impinges, lowers pressure along the periphery of the fog and in a two-way action of pushing and pulling causes hot gases from the enclosure to blowback past the nozzle area. Depending on direction of fog discharge and enclosure shape, these hot gases may scour one side of the nozzle area preferentially, or the top or bottom, instantly raising the temperature to hazardous levels and exhausting the oxygen.
According to objects of this invention, on demand a protective whirling cone of fog can be extended as a shield ahead of the firefighting team at the nozzle to confine and cool gaseous discharge from a blazing enclosure, and importantly, would tend to average out blowback temperature by the whirling, the whirl beating aside and breaking up hot currents of gases. Although fixed-multiple-outlet cone fogging nozzles are known they cannot provide the whirling-cone fogging action.
Further objects are to provide a system as described which is easy to use, unmistakable in operational adjustment under the most adverse circumstances, reliable, moderate in cost, adaptable in size, durable, and convenient to use, and which can be injected into an involved structure without subjecting the firefighter user to any more danger than necessary.